Help ID stuff on Liverock

[MarkoD]

i use RO/DI water religiously. but if they're good i guess ill just leave them alone

[christyf5]

I would just leave them alone. If you scrape them off the rock they'll just break into little bits with each little bit having the potential to settle and form a new colony somewhere. Like cale262 said, they are self limiting. Once they have nothing left to build colonies they'll start to disappear.